This invention relates to a controlled deflection roll such as is used in the press and calender sections of a papermaking machine. More particularly, this invention relates to a hydrostatic bearing pad for a controlled deflection roll.
As partially illustrated in FIGS. 5 and 6, a typical controlled deflection roll 110 includes a roll shaft 114 having a longitudinal axis 118 extending in the cross-machine direction. A roll shell 122 surrounds the shaft 114. The shell 122 engages another roll (not shown) to apply a nip pressure. One or more bearing pads 154 support the inner surface of the shell 122 relative to the shaft 114. Hydraulic fluid flows between the contact surface 158 of each bearing pad 154 and the inner surface of the shell 122. The side edges 164 of each contact surface 158 extend along planes perpendicular to the axis 118 of the shaft 114. A physical gap G.sub.PA (only two identified in FIG. 5) is defined between the side edges 164 of adjacent bearing pads 154, and the gaps G.sub.PA extend along planes perpendicular to the axis 118 of the shaft 114. Similarly, the contact surface 158 of each bearing pad 154 includes a plurality of continuous contact surface portions 174 (identified in FIGS. 5 and 6 for the left bearing pad 154 only) which extend the full length of the bearing pad 154 (from top to bottom in FIG. 5) and which extend perpendicular to the axis 118.